/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/****************************************************************************
 * tools/b16.c
 *
 *   Copyright (C) 2007-2012 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <stdio.h>
#include <stdlib.h>

/****************************************************************************
 * Private Functions
 ****************************************************************************/

static void show_usage(const char *progname)
{
	fprintf(stderr, "\nUSAGE: %s <b16_t>|<float>\n", progname);
	fprintf(stderr, "\nWhere:\n");
	fprintf(stderr, "  <b16_t>:\n");
	fprintf(stderr, "    A b16 fixed precision value in hexadecimal form: E.g., 0x00010000\n");
	fprintf(stderr, "    Any value begininning with '0' will assumed by be hexadecimal format\n");
	fprintf(stderr, "  <float>:\n");
	fprintf(stderr, "    A floating value in standard form: E.g., 5.1\n");
	exit(EXIT_FAILURE);
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/

int main(int argc, char **argv, char **envp)
{
	double fvalue;
	unsigned long ulvalue;
	long lvalue;
	const char *str;
	char *endptr;

	/* There must be exactly one argument */

	if (argc != 2) {
		fprintf(stderr, "\nExpected a single argument\n");
		show_usage(argv[0]);
	}
	str = argv[1];

	/* If the value begins with a zero, we will assume that it is a hexadecimal
	 * representation.
	 */

	if (str[0] == '0') {
		endptr = NULL;
		ulvalue = strtoul(str, &endptr, 16);
		if (!endptr || *endptr != '\0') {
			fprintf(stderr, "\nHexadecimal argument not fully converted\n");
			show_usage(argv[0]);
		}

		if (ulvalue >= 0x80000000)
			lvalue = ~ulvalue + 1;
		else
			lvalue = ulvalue;

		fvalue = ((double)lvalue) / 65536.0;
		printf("0x%08lx -> %10.5f\n", ulvalue, fvalue);
	} else {
		endptr = NULL;
		fvalue = strtod(str, &endptr);
		if (!endptr || *endptr != '\0') {
			fprintf(stderr, "\nFloating point argument not fully converted\n");
			show_usage(argv[0]);
		}

		lvalue = 65536.0 * fvalue;
		printf("%10.5f -> 0x%08lx\n", fvalue, lvalue);
	}

	return 0;
}
